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I posted the other day a question about my race motor which is a 01 Polaris 800 XCR.  The motor has 1 season on it.  I had lost 20 lbs of compression so I decided to pull the cylinders and rering the motor.  I found the top ring on each piston stuck.  It looked weard as.  Piston wash looked great, cylinder and piston looked great.  On closer inspection I notice the top edge of the exhaust port looks like the edge is buffed up or looks like it was chamfered.  So basically the exhaust port was hogged too wide and the ring is hooking the port.  I guess it's a good thing I found this before I had a catastrophic failure and junked my whole motor.  My question is would you go back to the performance company point it out and raise  or say  on it and call it a bad experiance.  Right now I am not very happy.  I don't want to start bad mouthing the company right away but as far as I am concerned they screwed up an made the exhaust port too wide.  Thanks for your input

PS it isn't a rinkey dink little outfit that did my porting.  It is a place that does tons of porting and dyno work.  It should never happen.

Riley

I would say you went to a good motor shop

You have a whole season on the motor and it sounds like you never had a cyl off

If port was too wide the cyl would have failed long ago

Race motor not trail (some maintanence required)

jackpot wrote:

I would say you went to a good motor shop You have a whole season on the motor and it sounds like you never had a cyl off If port was too wide the cyl would have failed long ago Race motor not trail (some maintanence required)

Jackpot to answer your questions

1 Yes it is a well known reputable performance company that everybody has heard of.  I didn't go the cheap route to save a buck.

2 It is strictly a race motor built for speed runs with very little time on it.

3 I never had no reason to pull a cylinder off untill the end of the winter when I discovered it was down 20 lbs of compression on all three cylinders and I did a Leak down test and if failed miserably.  I realize maintenance is requires on any motor.  My maintenance period is usually the Summer unless a problem appears.  With speed runs you don't put that many miles on.  I ran the sled at 5 speed runs through out the winter.  Plus I realize there are other types of racing that require way more maintenance then speed runs.

4 I run good race gas and oil.  It hooked the top ring just hard enough to stick the ring in.  The motor still had 150 lbs of compression and ran strong.  I am not trying to bash anybody yet.  I am basically a racer on a budget that built this motor figuring it would last a good couple of years.  That is why I chose this performance company because of the reputation they have.

5 Unfortunately this years budget does not have a new top end in it and will take me out for this season unless they stand in back of their reputation.

Riley

Riley

Sorry for jumping into this post

I am not one of the experts and  should not have been on this post in the first place

Good luck with your speed runs

Here is just a little follow up.  I went into Bikeman this morning and talked to Erich.  He took a look at my cylinders and agreed what my thoughts were about the ring hooking the exhaust port.  He called his guy who did my porting and talked to him about it.  This is the conclusion we came up with.  Erich chamfered the top edge of the exhaust port more and I am going back to OEM pistons which I had planned on doing anyway.  Hopefully it will hold up next year.  We will find out.  I would have to say Erich has been great to deal with through out building this motor.  I feel a little better now then I did when I found the problem.

Riley